2to3: apply `dict` fixer.

In Python3 `dict.items()`, `dict.keys()`, and `dict.values()` are
iterators. This causes problems when a list is needed so the 2to3 fixer
explicitly constructs a list when is finds on of those functions.
However, that is usually not necessary, so a lot of the work here has
been cleaning up those places where the fix is not needed. The big
exception to that is the `numpy/f2py/crackfortran.py` file. The code
there makes extensive use of loops that modify the contents of the
dictionary being looped through, which raises an error. That together
with the obscurity of the code in that file made it safest to let the
`dict` fixer do its worst.

Closes #3050.

1 files changed, 2 insertions, 2 deletions

diff --git a/numpy/distutils/npy_pkg_config.py b/numpy/distutils/npy_pkg_config.py
index 040ee632b..ceab906a4 100644
--- a/numpy/distutils/npy_pkg_config.py
+++ b/numpy/distutils/npy_pkg_config.py
@@ -143,7 +143,7 @@ class LibraryInfo(object):
             The list of section headers.
 
         """
-        return self._sections.keys()
+        return list(self._sections.keys())
 
     def cflags(self, section="default"):
         val = self.vars.interpolate(self._sections[section]['cflags'])
@@ -222,7 +222,7 @@ class VariableSet(object):
             The names of all variables in the `VariableSet` instance.
 
         """
-        return self._raw_data.keys()
+        return list(self._raw_data.keys())
 
     # Emulate a dict to set/get variables values
     def __getitem__(self, name):